.box {
	width: 23.4375rem;
	height: 47.6875rem;
	margin-left: auto;
	margin-right: auto;
	background-image: url(http://api.btstu.cn/sjbz/?lx=m_dongman);
	background-position: center center;
}
.choose{
	width: auto;
	height: auto;
	background-image: url((http://api.btstu.cn/sjbz/?lx=m_dongman);
	border-radius: 5rem;
	box-shadow: 0.375rem 0.4375rem 0.5rem;
	font-size: 3rem;
}
#x1,#x2,#x3,#x4{
	font-size: 3rem;
	width: auto;
	height: auto;
	box-shadow: 3rem 4rem 5rem;
	text-align: center;
	border-radius: 3rem;
}
#x1{
	color: red;
}
#x2{
	color: #00FFFF;
}
#x3{
	color: green;
}
